Martin St. Louis (center) celebrates his goal with teammates Derek Stepan (left) and Dan Girardi during the first period of the Rangers' 4-1 win over the Flyers Tuesday night. Photo: Bruce Bennett/Getty Images

PHILADELPHIA — Hours after he was announced as one of the finalists for the Lady Byng Trophy — which is awarded to the NHL player who has “exhibited the best type of sportsmanship and gentlemanly conduct combined with a high standard of playing ability” — Martin St. Louis was anything but gentlemanly to the Flyers on Tuesday night.

The Rangers forward, who endured 19 frustrating regular-season games with only one goal after he was acquired in a trade-deadline deal with Tampa Bay, delivered a dagger to Philadelphia in a 4-1 Rangers win in Game 3 at the Wells Fargo Center.

It was St. Louis’ goal at 10:24 of the first period — a redirect of a Dan Girardi shot from right point — that gave the Rangers a 2-0 lead and quieted what had been a raucous home building for the Flyers.
It was St. Louis’ second goal in the last two playoff games and it doubled his regular-season output — just three games into the postseason.

Rangers center Brad Richards, who played with St. Louis in Tampa Bay, where they won a Stanley Cup together, has seen firsthand the 38-year-old St. Louis’ struggle to fit in with his new team. The two are close friends and St. Louis has spent a lot of time staying at Richards’ home.

“It was very difficult for him,’’ Richards said. “He left a place he’d been for 13 years and everything was new. He also knew he wasn’t coming here for only a short time. You know you got traded for a captain [Ryan Callahan]. You know it’s an Original Six market. There was nothing he wanted to do more than play well as a Ranger and he probably just tried a little too hard and it got to him.

“It’s good for him to finally calm down and reset. He’s getting more comfortable every day and back to being Marty. Now, you’re going to see the real Marty St. Louis.’’

Said St. Louis, “You always want to be on top of your game. It’s a tough thing to do consistently. I want to be helping. You’re just trying to play a total game this time of year.’’

The fact St. Louis has found his scoring groove in the playoffs should come as no surprise considering he is one of only six active players to average at least a point per game in the playoffs among players who have played 50 or more postseason games.

He has been awarded the Lady Byng Trophy in three of the last four seasons and has been a finalist for the prestigious honor in eight of the last 10 years.

“It’s an honor to be nominated for any award,” St. Louis said. “But I think my focus is on something bigger and better right now.”